Clinical and prognostic implications of capillary density in patients with cardiac light chain amyloidosis.

aimsCardiac involvement is crucial factor determining outcomes of light chain (AL) amyloidosis. This study evaluated whether capillary density (CD) quantified from endomyocardial biopsy is associated with structural and functional parameters of amyloid heart. Also, we investigated whether capillary density improves the prognostic value of the current staging system in AL amyloidosis patients with cardiac involvement. METHODS AND

resultsA total of 67 patients with biopsy-proven AL cardiac amyloidosis were prospectively enrolled in this study. All patients underwent transthoracic echocardiography and EBM at the time of diagnosis. Left ventricle global longitudinal strain was evaluated on two-dimensional strain echocardiography. The primary endpoint was all-cause mortality. Amyloid load and capillary density were calculated on endomyocardial biopsy stained immunohistochemically with antibody against amyloid P and CD31, respectively. Among the study population, 37 patients (55.2%) were classified as Stage IV, and the cumulative incidence of death at 1 year was 34% (23 patients). A total of 65 (97%) patients underwent chemotherapy. CD showed a significant correlation with left ventricle global longitudinal strain (r = 0.274, P = 0.025), log N-terminal pro-B type natriuretic peptide (r = -0.311, P = 0.005), and amyloid load (r = -0.438, P < 0.001). Patients with a CD ≤ 220/mm

conclusionsCapillary density was significantly related to the severity of amyloid deposits in the myocardium and showed incremental prognostic value in addition to the 2012 Mayo staging system.